Dwyane Wade continued to look old and creaky. Chris Bosh, who earlier in the day promised a victory, came up empty on all accounts. And Ray Allen, thrust into the starting lineup in place of the slumping Mario Chalmers, made only one field goal.

James had a game-high 31 points to go with 10 rebounds, 5 assists and 2 blocks, and he helped limit Tony Parker to one basket through three quarters. But it was not nearly enough for him to stop the Spurs on his own.

“They were the much better team,” James said. “That’s how team basketball should be played. You know, it’s selfless. Guys move, cut, pass; you’ve got a shot, you take it. But it’s all for the team, and it’s never about the individual. That’s the brand of basketball, and that’s how team basketball should be played.”

The compliment by James is likely to be parsed, dissected and interpreted in the coming weeks as he decides whether to remain with Miami or opt out of his contract and test the free-agent market this off-season.

Wade and Bosh are in the same position, and there has been speculation that the three would take pay cuts so the Heat could add the Knicks’ Carmelo Anthony, who also has an opt-out clause in his contract. Houston forward Chandler Parsons offered another opinion when he said Friday that he thought James would leave Miami — perhaps to head back to Cleveland.

“I will deal with my summer when I get to that point,” James said. “Me and my team will sit down and deal with it. I love Miami. My family loves it. But obviously right now that’s not even what I’m thinking about. You guys are trying to find answers. I’m not going to give you one.”

Bosh and Wade did not provide any answers, either.

Bosh, who made the go-ahead 3-pointer in Game 2, missed his last nine shots from behind the arc in the series. Wade, who missed 28 games in the regular season to rest his chronically sore knees, shot 7 of 25 from the field over the last two games.

Their ineffectiveness was apparent in a handful of plays, the type that might best express a will to win. After Manu Ginobili dunked over Bosh to bring a stunned arena to life, Wade tried to return the favor. But Tiago Splitter interfered with the plan and blocked Wade’s dunk attempt.

A last gasp by the Heat ended fittingly enough when Wade and Bosh bungled an alley-oop that would have closed the gap to 16 points with 5 minutes 45 seconds left. The Spurs grabbed the rebound, and Tony Parker raced to the other end for a layup.

“They dominated us,” Bosh said. “They took two games on our home court by 20 points apiece. They beat us by 20 tonight. It hasn’t been much of a series, not even close. They played the best basketball I’ve ever seen.”

Wade sounded almost wistful as he sat next to James at the postgame news conference, reflecting on the four seasons they had spent as teammates, which included an awkward beginning, two championships and a continual turn in the spotlight.

“We didn’t know what to expect when we decided to become teammates years ago,” Wade said. “We just knew that we felt as individuals that we could do it, that we could put our egos to the side and not care about the individual part of the game.”

If the Heat’s Big 3 decide to stay together, if Wade is not on a severe downward slope at age 32, and if the Heat’s defense has not been exposed with Bosh at center, then they will at least need more help. Shane Battier is retiring, and perhaps Allen will as well.

The Spurs, among other things, displayed the importance of developing a deep bench with complementary parts.

There was no such relief for James. The series began with him suffering cramps when the air-conditioning system failed at AT&T Center. It ended with James finding himself unable to carry the weight of the entire team.

Correction:

An earlier version of this article misstated Chris Bosh's 3-point shooting in Sunday's game. He missed all five of his 3-point attempts Sunday, not his last nine of the game. (He had missed his last nine long-range attempts of the series.)